kernel.git/drivers/lightnvm/pblk-init.c, branch linux-5.4.y

lightnvm: pblk: use kvmalloc for metadata

2019-08-06T14:20:10Z

There is no reason now not to use kvmalloc, so replace the internal metadata allocation scheme. Reviewed-by: Javier González Reviewed-by: Christoph Hellwig Signed-off-by: Hans Holmberg Signed-off-by: Jens Axboe

lightnvm: pblk: IO path reorganization

2019-05-06T16:19:19Z

This patch is made in order to prepare read path for new approach to partial read handling, which is simpler in compare with previous one. The most important change is to move the handling of completed and failed bio from the pblk_make_rq() to particular read and write functions. This is needed, since after partial read path changes, sometimes completed/failed bio will be different from original one, so we cannot do this any longer in pblk_make_rq(). Other changes are small read path refactor in order to reduce the size of the following patch with partial read changes. Generally the goal of this patch is not to change the functionality, but just to prepare the code for the following changes. Signed-off-by: Igor Konopko Reviewed-by: Javier González Signed-off-by: Matias Bjørling Signed-off-by: Jens Axboe

lightnvm: pblk: fix bio leak when bio is split

2019-05-06T16:19:17Z

For large size io where blk_queue_split needs to be called inside pblk_rw_io, results in bio leak as bio_endio is not called on the newly allocated. One way to observe this is to mounting ext4 filesystem on the target and issuing 1MB io with dd, e.g., dd bs=1MB if=/dev/null of=/mount/myvolume. kmemleak reports: unreferenced object 0xffff88803d7d0100 (size 256): comm "kworker/u16:1", pid 68, jiffies 4294899333 (age 284.120s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 60 e8 31 81 88 ff ff .........`.1.... 01 40 00 00 06 06 00 00 00 00 00 00 05 00 00 00 .@.............. backtrace: [<000000001f5aa04f>] kmem_cache_alloc+0x204/0x3c0 [<0000000040945aab>] mempool_alloc_slab+0x1d/0x30 [<00000000b4959ab4>] mempool_alloc+0x83/0x220 [<00000000646bad9b>] bio_alloc_bioset+0x229/0x320 [<000000009264b251>] bio_clone_fast+0x26/0xc0 [<0000000008250252>] bio_split+0x41/0x110 [<00000000e365cad0>] blk_queue_split+0x349/0x930 [<00000000eb5426bc>] pblk_make_rq+0x1b5/0x1f0 [<00000000eea09cec>] generic_make_request+0x2f9/0x690 [<00000000ae6acede>] submit_bio+0x12e/0x1f0 [<00000000f9b8b82a>] ext4_io_submit+0x64/0x80 [<000000009e4f817d>] ext4_bio_write_page+0x32e/0x890 [<00000000cbd0d106>] mpage_submit_page+0x65/0xc0 [<000000000eec7359>] mpage_map_and_submit_buffers+0x171/0x330 [<000000009a7afcb6>] ext4_writepages+0xd5e/0x1650 [<000000004476b096>] do_writepages+0x39/0xc0 In case there is a need for a split, blk_queue_split returns the newly allocated bio to the caller by changing the value of pointer passed as a reference, while the original is passed to generic_make_requests. Although pblk_rw_io's local variable bio* has changed and passed to pblk_submit_read and pblk_write_to_cache, work is done on this new bio*, and pblk_rw_io returns NVM_IO_DONE, pblk_make_rq calls bio_endio on the old bio* because it passed bio pointer by value to pblk_rw_io. pblk_rw_io is unfolded into pblk_make_rq so that there is no copying of bio* and bio_endio is called on the correct bio*. Signed-off-by: Chansol Kim Reviewed-by: Javier González Signed-off-by: Matias Bjørling Signed-off-by: Jens Axboe

lightnvm: pblk: cleanly fail when there is not enough memory

2019-05-06T16:19:17Z

L2P table can be huge in many cases, since it typically requires 1GB of DRAM for 1TB of drive. When there is not enough memory available, OOM killer turns on and kills random processes, which can be very annoying for users. This patch changes the flag for L2P table allocation on order to handle this situation in more user friendly way. GFP_KERNEL and __GPF_HIGHMEM are default flags used in parameterless vmalloc() calls, so they are also keeped in that patch. Additionally __GFP_NOWARN flag is added in order to hide very long dmesg warn in case of the allocation failures. The most important flag introduced in that patch is __GFP_RETRY_MAYFAIL, which would cause allocator to try use free memory and if not available to drop caches, but not to run OOM killer. Signed-off-by: Igor Konopko Reviewed-by: Hans Holmberg Reviewed-by: Javier González Signed-off-by: Matias Bjørling Signed-off-by: Jens Axboe

lightnvm: pblk: reduce L2P memory footprint

2019-05-06T16:19:16Z

Currently L2P map size is calculated based on the total number of available sectors, which is redundant, since it contains mapping for overprovisioning as well (11% by default). Change this size to the real capacity and thus reduce the memory footprint significantly - with default op value it is approx. 110MB of DRAM less for every 1TB of media. Signed-off-by: Igor Konopko Reviewed-by: Hans Holmberg Reviewed-by: Javier González Signed-off-by: Matias Bjørling Signed-off-by: Jens Axboe

lightnvm: pblk: Switch to use new generic UUID API

2019-02-11T15:18:07Z

There are new types and helpers that are supposed to be used in new code. As a preparation to get rid of legacy types and API functions do the conversion here. Signed-off-by: Andy Shevchenko Reviewed-by: Javier González Signed-off-by: Matias Bjørling Signed-off-by: Jens Axboe

lightnvm: pblk: stop taking the free lock in in pblk_lines_free

2019-02-11T15:18:07Z

pblk_line_meta_free might sleep (it can end up calling vfree, depending on how we allocate lba lists), and this can lead to a BUG() if we wake up on a different cpu and release the lock. As there is no point of grabbing the free lock when pblk has shut down, remove the lock. Signed-off-by: Hans Holmberg Signed-off-by: Matias Bjørling Signed-off-by: Jens Axboe

lightnvm: pblk: support packed metadata

2018-12-11T19:22:35Z

pblk performs recovery of open lines by storing the LBA in the per LBA metadata field. Recovery therefore only works for drives that has this field. This patch adds support for packed metadata, which store l2p mapping for open lines in last sector of every write unit and enables drives without per IO metadata to recover open lines. After this patch, drives with OOB size <16B will use packed metadata and metadata size larger than16B will continue to use the device per IO metadata. Reviewed-by: Javier González Signed-off-by: Igor Konopko Signed-off-by: Matias Bjørling Signed-off-by: Jens Axboe

lightnvm: disable interleaved metadata

2018-12-11T19:22:35Z

Currently pblk only check the size of I/O metadata and does not take into account if this metadata is in a separate buffer or interleaved in a single metadata buffer. In reality only the first scenario is supported, where second mode will break pblk functionality during any IO operation. This patch prevents pblk to be instantiated in case device only supports interleaved metadata. Reviewed-by: Javier González Signed-off-by: Igor Konopko Signed-off-by: Matias Bjørling Signed-off-by: Jens Axboe

lightnvm: dynamic DMA pool entry size

2018-12-11T19:22:35Z

Currently lightnvm and pblk uses single DMA pool, for which the entry size always is equal to PAGE_SIZE. The contents of each entry allocated from the DMA pool consists of a PPA list (8bytes * 64), leaving 56bytes * 64 space for metadata. Since the metadata field can be bigger, such as 128 bytes, the static size does not cover this use-case. This patch adds support for I/O metadata above 56 bytes by changing DMA pool size based on device meta size and allows pblk to use OOB metadata >=16B. Reviewed-by: Javier González Signed-off-by: Igor Konopko Signed-off-by: Matias Bjørling Signed-off-by: Jens Axboe